Processing subscriber data regarding services available to a subscriber in a visited area

ABSTRACT

A mobile communication system includes a home location register that transmits an inquiry to the visitor location register about services supported by the visitor location register in response to receiving a location update message, receives a reply from the visitor location register, determines the services supported by the visitor location register based on the reply received from the visitor location register and transmits information to the visitor location register on services that, according to the information stored in the home location register, are available to the subscriber and that are supported by the visitor location register. Similarly, the visitor location register receives the inquiry about the services from the home location register, transmits the information to the home location register on the services supported by the visitor location register in response to the inquiry, and receives the transmitted information.

This is a National Stage application of International Application No.PCT/F100/01050, which was filed on Nov. 30, 2000, which designated theU.S., and was filed in the English language.

The present invention is related to updating the subscriber service datain a mobile communication system. The invention relates particularly toservices available to a user and to transmitting information on therange of services when a mobile station moves in the mobilecommunication network.

In the GSM (Global System for Mobile Communications) system, forexample, a previously known solution is, when a mobile station moves inthe mobile communication network from the coverage area of one mobileservices switching centre to the coverage area of another mobileservices switching centre, to transmit subscriber data includinginformation on services available to the subscriber from the homelocation register to the visitor location register of the mobileservices switching centre in whose coverage area the mobile station islocated at the particular moment. This transmission of information iscarried out in connection with location update for example in such amanner that the home location register transmits a list of servicesavailable to the subscriber, and, subsequently, the visitor locationregister indicates whether there are such services included that cannotbe implemented in the area of the mobile services switching centrecorresponding to the visitor location register. Consequently, theseservices must be modified or replaced with other services.

A problem of the above-described system is that when the home locationregister transmits the list of services available to the subscriber itdoes not know which services the visitor location register supports. Notuntil the home location register has received a notification that thevisitor location register does not support one or more services includedin the list transmitted by the home location register can the homelocation register replace the services not supported by the visitorlocation register for example by modifying the additional features ofthe services and try to retransmit the service information. At worst,this sequence of transmissions can be repeated several times until onlyservices that are supported by the visitor location register areincluded in the list. This causes additional transmissions of messagesand also possible unnecessary costs. It is also extremely complex toprogram the system because the replacement procedure of the servicesmust be taken into account.

An object of the invention is to solve the problem described above byproviding a solution by means of which information on services availableto the subscriber can be transmitted more flexibly from the homelocation register to the visitor location register and information onservices not supported by the visitor location register can be bettertaken into account. This object is achieved by a method for processingsubscriber service data in a mobile communication system, which methodcomprises receiving a location update message for a mobile subscriber ata home location register, selecting at the home location register theservices that are supported by a visitor location register and,according to the information stored in the home location register,available to a subscriber, and transmitting from the home locationregister to the visitor location register a list of the selectedservices. Said method is characterized in that in order to provide thehome location register with information about services supported by thevisitor location register the method comprises the steps of transmittingan inquiry from the home location register to the visitor locationregister about services supported by the visitor location register,transmitting an answer to the inquiry from the visitor location registerto the home location register, the answer containing information on theservices supported by the visitor location register.

The invention is based on the idea that by transmitting information tothe home location register on services supported by the visitor locationregister of the mobile services switching centre in whose area themobile station is located, a list including only services that,according to the home location register, are available to the subscriberand that are supported by the visitor location register can betransmitted to the visitor location register by one message. Theinformation on the services supported by the visitor location registeris obtained such that after location update, the home location registertransmits an inquiry to the visitor location register about servicessupported by the visitor location register. The visitor locationregister replies to the inquiry. Not until the home location registerhas received the information on the services supported by the visitorlocation register does the home location register transmit a list ofservices offered for the use of the subscriber.

Another object of the invention is to provide a mobile communicationsystem where the method of the invention can be utilized such thatinformation on services available to the subscriber can be transmittedmore flexibly from the home location register to the visitor locationregister. This object is achieved with a mobile communication systemcomprising at least a first and a second mobile services switchingcentre and, in order to store subscriber data, a home location registerhaving a data transmission connection to the first mobile servicesswitching centre, and a visitor location register having a datatransmission connection to the second mobile services switching centre,in which visitor location register information on mobile stationslocated in the coverage area of the second mobile services switchingcentre is maintained, wherein said home location register comprisesmeans for transmitting information to the visitor location register onservices that, according to the information stored in the home locationregister, are available to a subscriber and that are supported by thevisitor location register, and said visitor location register comprisesmeans for receiving the information transmitted by the home locationregister on the services available to the subscriber and supported bythe visitor location register. Said mobile communication system ischaracterized in that the home location register comprises means fortransmitting an inquiry to the visitor location register about servicessupported ported by the visitor location register in response toreceiving a location update message, means for receiving a reply fromthe visitor location register and means for finding out the servicessupported by the visitor location register on the basis of the replyreceived from the visitor location register, and the visitor locationregister comprises means for receiving the inquiry about the servicesfrom the home location register, and means for transmitting theinformation to the home location register on the services supported bythe visitor location register in response to the inquiry.

Another object of the invention is to provide a home location registerof a mobile communication network, which home location register can beutilized in a mobile communication system in accordance with the presentinvention, such that information on services available to the subscribercan be transmitted more flexibly from the home location register to thevisitor location register. This object is achieved with a home locationregister of a mobile communication network, in which home locationregister subscriber data on mobile subscribers registered in the networkis maintained, the subscriber data comprising information on servicesavailable to the subscriber, which home location register comprisesmeans for transmitting information to a visitor location register onservices that, according to the information stored in the home locationregister, are available to the subscriber and that are supported by thevisitor location register. The home location register of the inventionis characterized in that the home location register comprises means fortransmitting an inquiry to the visitor location register about servicessupported by the visitor location register in response to receiving alocation update message, means for receiving a reply from the visitorlocation register, and means for finding out the services supported bythe visitor location register on the basis of the reply received fromthe visitor location register.

Another object of the invention is to provide a visitor locationregister of a mobile communication network, which visitor locationregister can be utilized in a mobile communication system in accordancewith the invention, such that information on services available to thesubscriber can be transmitted more flexibly from the home locationregister to the visitor location register. This object is achieved witha visitor location register of a mobile communication network, in whichvisitor location register information necessary for transmitting callson mobile subscribers located in the coverage area of a mobile servicesswitching centre at a given time is maintained, which visitor locationregister comprises means for receiving information transmitted by thehome location register on services available to a subscriber andsupported by the visitor location register. The visitor locationregister of the invention is characterized in that the visitor locationregister comprises means for receiving an inquiry about services from ahome location register, and means for transmitting information to thehome location register on the services supported by the visitor locationregister in response to the inquiry.

Hence, the most significant advantages of the system and apparatus ofthe invention are that the number of messages to be transmitted isreduced and complex sequences of replacements of services can beavoided. Information about a correct range of services can thus betransmitted to the visitor location register in a faster and simplermanner.

The preferred embodiments of the mobile communication system and homelocation register of the invention are disclosed in the attacheddependent claims.

The invention is now described in closer detail with reference toattached drawings, in which

FIG. 1 shows a flow chart of a method in accordance with the invention,and

FIG. 2 shows a block diagram of a mobile communication system inaccordance with the invention.

FIG. 1 shows a flow chart of a method in accordance with the invention.When the mobile station moves from the coverage area of the first mobileservices switching centre to the coverage area of the second mobileservices switching centre, the mobile station detects in step 1A thatthe location area has changed. This results in location update. Thevisitor location register inquires identification data on the subscriberof the mobile station and in step 1B a location update message isreceived at the home location register. When the home location registerhas received the location update message, the information about theservices available to the mobile subscriber must be transmitted from thehome location register to the visitor location register by a message.Services included can be, for example, in accordance with part 09.02 ofthe GSM specification, in which case the MAP_INSERT_SUBSCRIBER_DATAmessage used comprises the following parameters:

Invoke Id

IMSI

MSISDN

Category

Subscriber Status

Bearer Service List

Teleservice List

Forwarding Information List

Call Barring Information List

CUG Information List

SS-Data List

Operator Determined Barring General Data

Operator Determined Barring HPLMN Data

Roaming Restriction Due To Unsupported Feature

Regional Subscription Data

SS-Code List

Regional Subscription Response

User Error

Provider Error.

In step 1C inquiry transmission means of the home location registertransmit an inquiry to inquiry reception means of the visitor locationregister about services supported by the visitor location register. Instep 1D reply transmission means of the visitor location registertransmit the information on the services supported by the visitorlocation register to reply reception means of the home locationregister. Subsequently, in step 1E, service selection means of the homelocation register find out, after receiving the reply from the visitorlocation register, which services are supported by the visitor locationregister and, according to the information stored in the home locationregister, available to the subscriber. In step 1F selection resulttransmission means of the home location register transmit a list of theselected services to selection result reception means of the visitorlocation register. This list comprises only services supported by thevisitor location register, so there is no need for retransmissions orreplacement procedures.

The home location register HLR can transmit the list of the servicesthat are available to the subscriber as a MAP_INSERT_SUBSCRIBER_DATAmessage in accordance with part 09.02 of the GSM specification, themessage including a bearer service list, teleservice list, forwardinginformation list, call barring information list and closed user groupinformation list CUG, for example.

FIG. 2 shows a block diagram of a mobile communication system inaccordance with the invention, the mobile communication system being acellular GSM system in the present example.

The mobile communication system described comprises a mobile station MS,two base transceiver stations BTS1 and BTS2, two base stationcontrollers BSC1 and BSC2, two mobile services switching centres MSC1and MSC2, and a home location register HLR having a data transmissionconnection to the first mobile services switching centre MSC1 and avisitor location register VLR having a data transmission connection tothe second mobile services switching centre MSC2. The bidirectionalarrow in the figure designates a radio connection.

The home location register HLR comprises inquiry transmission means 1for transmitting an inquiry to the visitor location register VLR aboutservices supported by the visitor location register VLR, reply receptionmeans 2 for receiving the answer of the inquiry from the visitorlocation register VLR, service selection means 3 for finding out theservices supported by the visitor location register VLR and available tothe subscriber and selection result transmission means 4 fortransmitting a list of the selected services to the visitor locationregister VLR. The visitor location register VLR comprises inquiryreception means 5 for receiving the inquiry from the home locationregister HLR, reply transmission means 6 for transmitting theinformation on the services supported by the visitor location registerVLR to the home location register HLR and selection result receptionmeans 7 for receiving the list of selected services from the homelocation register HLR.

In practice, all means presented as blocks 1 to 7 of the home locationregister HLR and the visitor location register VLR can be implemented byone or more computer programs.

It is obvious to those skilled in the art that as technology progressesthe basic idea of the invention can be implemented in many ways. Theinvention and its embodiments are thus not restricted to the examplesdisclosed above but they can vary within the scope of the claims.

1. A method for processing subscriber service data in a mobilecommunication system, the method comprising: receiving a location updatemessage for a mobile subscriber at a home location register; selecting,at the home location register, services that are supported by a visitorlocation register and which are, according to the information stored inthe home location register, available to a subscriber; and transmitting,from the home location register to the visitor location register, a listof the selected services; transmitting an inquiry from the home locationregister to the visitor location register regarding services supportedby the visitor location register; and in response to the inquiry,transmitting an answer from the visitor location register to the homelocation register, the answer containing information relating to theservices supported by the visitor location register.
 2. A mobilecommunication system, comprising: at least a first and a second mobileservices switching center; a home location register configured to storesubscriber data and having a data transmission connection to the firstmobile services switching center, and a visitor location register havinga data transmission connection to the second mobile services switchingcenter, said visitor location register maintaining visitor locationregister information concerning mobile stations located in the coveragearea of the second mobile services switching center, wherein said homelocation register comprises means for transmitting information to thevisitor location register concerning services that, according toinformation stored in the home location register, are available to asubscriber and that are supported by the visitor location register,wherein said visitor location register comprises means for receiving theinformation transmitted by the home location register, wherein the homelocation register comprises: means for transmitting an inquiry to thevisitor location register about services supported by the visitorlocation register in response to receiving a location update message,means for receiving a reply from the visitor location register, andmeans for finding out the services supported by the visitor locationregister on the basis of the reply received from the visitor locationregister, and wherein the visitor location register comprises: means forreceiving the inquiry about the services from the home locationregister, and means for transmitting the information to the homelocation register concerning the services supported by the visitorlocation register in response to the inquiry.
 3. The system of claim 2,wherein said at least a first and a second mobile services switchingcenter are configured to operate in a GSM system.
 4. The communicationsystem of claim 2, wherein said means for transmitting information tothe visitor location register transmits said information by aMAP_INSERT_SUBSCRIBER_DATA message in accordance with part 09.02 of theGSM specification.
 5. A method for processing subscriber service data ina mobile communication system, the method comprising, in the orderindicated: receiving, at a home location register (HLR), a locationupdate message relating to a mobile subscriber; next, in response to thelocation update message, inquiring about services supported by anassociated visitor location register (VLR); in response to the inquiry,transmitting information to the HLR relating to services supported bythe associated VLR; then, based upon both the services supported by theassociated VLR and specific subscriber services available to the mobilesubscriber at the HLR, transmitting, from the HLR, a list of selectedsubscriber services to the associated VLR.
 6. A mobile communicationsystem, comprising: a first mobile services switching center and asecond mobile services switching center; a home location register (HLR)having data transmission connectivity to the first mobile servicesswitching center, said HLR being configured to store subscriber serviceinformation relating to a specific mobile subscriber and to receive alocation update message relating to the specific mobile subscriber; avisitor location register (VLR) having data transmission connectivity tothe second mobile services switching center, said VLR being configuredto maintain VLR information concerning mobile stations located in acoverage area of the second mobile services switching center, to firstreceive an inquiry from the HLR regarding services supported by the VLR,and then to respond to the inquiry by identifying services that aresupported by the VLR to the HLR; wherein said HLR transmits specificsubscriber information to the VLR concerning services that are bothavailable to the specific mobile subscriber and that have beenidentified as being supported by the VLR.